Worked on security hardening for the byrnHDF/hdf5 repository, focusing on preventing buffer overflows in the HDF5 cache path. Addressed critical vulnerabilities by implementing robust buffer size checks during cache serialization and cache image header decoding, ensuring that memory reads and writes remained within allocated boundaries. Utilized C programming and security best practices to fix OSV-2024-390 and OSV-2023-77, reducing the risk of memory corruption and improving overall stability. The work involved detailed bug fixing and buffer overflow prevention, enhancing the safety of cache handling routines and contributing to more reliable and secure data processing within the codebase.